The effect of the lower and upper interface on properties of InAs/GaAs quantum dots

0433917 - FZÚ 2015 GR eng A - Abstrakt
Zíková, Markéta - Hospodková, Alice - Kubištová, Jana - Pangrác, Jiří - Komninou, Ph. - Kioseoglou, J. - Florini, N. - Drbohlav, Ivo
The effect of the lower and upper interface on properties of InAs/GaAs quantum dots.
iib2013 Book of Abstracts. Thessaloniki: Aristotle University of Thessaloniki, 2013 - (Komninou, P.)
[International Conference on Intergranular and Interphase Boundaries in Materials /14./. 23.06.2013-28.06.2013, Halkidiki]
Grant CEP: GA ČR GA13-15286S; GA MŠMT 7AMB12GR034
Institucionální podpora: RVO:68378271
Klíčová slova: interface * quantum dot * MOVPE
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus

The influence of lower and upper interface on InAs/GaAs quantum dot formation, shape and size was investigated on samples prepared by low pressure metal organic vapour phase epitaxy. A good epitaxial surface planarity is required for QD formation with high QD density and narrow size distribution. Therefore the growth conditions of QD buffer layer are very important. The QD size distribution and homogeneity was improved when the growth rate of the buffer layer was twice decreased. The upper QD interface is formed during the covering process. InAs/GaAs quantum dots were covered by GaAs or by GaAsSb. In the case of GaAs covering layer, the interface between InAs and GaAs forms InGaAs layer with gradual decrease of In concentration. The presence of Sb in covering layer helps to form very sharp interface between InAs and covering layer. GaAsSb also prevents dissolution of QDs during covering process, which can significantly influence QD PL properties.
Trvalý link: http://hdl.handle.net/11104/0238106